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A3 t�4 j Quik Stop Market No. 132 August 28, 1990 Job No. 349132-31 Page 3 Two borings, one on the north and one on the south side of the tank complex, will be drilled to groundwater and will be used to assess soil contamination only. Exceltech will attempt to collect relatively undisturbed soil samp;es from beneath the in-place fuel storage tanks to assess the soil condition there. Should more soil charactedzatiogi be necessary, Exceltech will determine the horizontal and vertical extent with further soil borings. Once the extent of hydrocarbon contamination has been found, the soil can be excavated where applicable. Soil analysis will determine the extent of excavation, Samples from the sidewalls will be taken every 20 feet,two to six samples will be taken from the bottom of the excavation (dependent upon size) and every corner will be sampled at the base of the excavation. This proposed exploration program will provide information which will help Exceltech assess the conditions of the soil and groundwater beneath the site. Exploratory Drilling and Soil Sampling Before field work begins, Exceltech will determine utility locations by contact Underground Services Alert. Exceltech will drill five borings at the approximate locations shown on Figure 2. The locations were selected in an attempt to assess the vertical and horizontal limit of soil and groundwater contamination. Th;, borings for 3.t the monitoring wells will be drilled with an Exceltech truck-mounted drill rig using J, hollow-stern auger to approximately 10 feet below the water table. The soil borings will be drilled to approximately 17 feet(the approximate depth to groundwater) with an Exceltech drill rig using holIow-stem auger. The auger and other tools used in the hole will be steam-cleaned before use to minimize the possibility of cross-contamination. Relatively undisturbed soil samples will be collected at 5-foot-depth intervals using a modified California split-spoon sampler equipped with three internal brass tubes,each 6 inches long and 2 inches in diameter. The sampler will be advanced 18 inches into undisturbed soil.with. a 140-pound hammer. Samples taken below water level will be collected using a 1-1/2-inch-inside-diameter, standard penetration sampler. This type of sampler has no internal brass liners and will be used primarily for soil logging. All soil cuttings from the drilling will ba,placed on and covered with plastic sheeting and left at the site. Once analytical resuIt., are known, the soil can be disposed of properly by �. Quik Stop. After recovery from the borehole the sampler will be disassembled and one sample � i _ liner will be preserved for chemical analysis in the following manner. Both ends of the liner will be covered with aluminum foil and a plastic cap. It will then be labeled with r ;` a unique sample number and pertinent sample information, placed in a plastic Zip bag, entered on a chain-of-custody form, and packed itk a chilled ice chest for transport to.a laboratory certified by the State of California. See Appendix A for.the Exceltech 1 E soil sampling protocol and laboratory procedures. two - - l